This study was conducted in order to suggest methods to develop a sound suppressing one's appetite and use it practically and to lay a foundation for continuous researches and developments. This study on suppressing one's appetite is aimed at providing overweight or obese individuals with assistances for losing weight. This study is based on the principle of conditioned reflex, and it traces wave analyses of the sound suppressing one's appetite and hormone actions on digestive organs. In this study, it is important to select, record, and analyze a sound that is effective for suppressing one's appetite. Also, it should be proved that the sound stimulating associated parts of the brain suppresses one's appetite by recalling memories stored by direct or indirect experiences. Therefore, the principle of conditioned reflex has been selected as the main research method, and wave analyses have increased the reliability of this study and shown images and flowcharts indicating how a sound suppressing the appetite is recorded and applied in one's body. This study is significant as it draws a conclusion that the sound can suppress one's appetite by producing physical and psychological reactions and suggest methods for practical uses.